Nowadays, more and more posts on how to teach people about health are on the Internet. The content of how to drink water is getting a lot of attention. For example, water can't be drunk overnight, cold water is longer than a chronic poison, and repeated boiled water can cause cancer. Many of these claims have been heard by people. Are these contents true?
Question one: How long should the water be consumed after boiling?
Che Zhenming said: "(The thermos) has a good warming effect, and when it is over 80 degrees, the water is absolutely safe. The temperature above 80 degrees has the effect of killing microorganisms."
Professor Che said that after the water temperature drops to 60 degrees, the water environment is very suitable for the breeding of bacteria. When microorganisms in the air enter the water, they will breed rapidly. It is best to finish drinking water before bacteria multiply. Professor Car recommends:
First, when it is cold, do not open it completely. At least one lid can reduce the entry of microorganisms;
Second, when the water temperature falls below 60 degrees, no more than 4 hours of storage.
Question 2: Can the water that is repeatedly boiled still drink?
Someone said on the Internet that the water that is repeatedly boiled cannot be used again. This will lead to excessive levels of nitrite in the water and possible carcinogenic effects. Is this claim reliable?
In this regard, Professor Che Zhenming said: "(Reheat water) minerals will be reduced, there will be no damage to the quality of water itself, it can only play the role of heating, sterilization, sterilization, will not have the quality of water influences."
Professor Che said that as long as it is not cold water that has been placed for a long time, repeated boiled water will not have an impact on human health. As for the so-called nitrite cancer, there is no basis.
Question 3: Drinking fountains and bottled mineral water, how long it is safe to drink?
Professor Che Zhenming stated: “Generally speaking, it is recommended to drink cold water (bottled mineral water) directly within one week (drinking a bucket of water). It is safe to drink within 4 hours after opening bottled mineral water.” Professor Che also suggested that when using a drinking fountain to drink water, it is best to drink boiled water, because the water dispenser is placed for a long time, the amount of cold water microorganisms is likely to exceed the standard.
In addition to the above three issues, Professor Che has also rejected the claim that people on the Internet must burn three minutes of boiling water to volatilize chlorine. He said that chlorine is a very volatile gas. When the water temperature reaches 30 degrees Celsius, its evaporation rate is already very fast. As long as the water temperature reaches a hundred degrees, the water will be completely free of chlorine.
